1. Field
One or more embodiments described herein relate to a display device.
2. Description of the Related Art
Various types of flat panel displays have been developed. Examples include liquid crystal displays, plasma displays, and organic light emitting diode (OLED) displays.
OLED displays include a display panel, a data driver, and a scan driver. The display panel has pixels at intersections between data lines and scan lines. The data driver supplies data voltages to the data lines, and the scan driver provides scan signals to the scan lines. The display panel also includes a power supply unit to one or more supply power voltages. When a scan signal is provided, each of the pixels controls current from a power voltage line to the OLED depending on a data voltage supplied through the data line. As a result, the OLED emits light with a predetermined level of luminance.
Because the first power voltage line which supplies the power voltage is coupled to the pixels, the power voltage drops due to IR drop when current is supplied to the pixels. That is, the IR drop causes a difference between the power voltage supplied to the pixels coupled to the first scan line and the power voltage supplied to the pixels coupled to an i-th scan line. Consequently, luminance varies depending on positions of the pixels, e.g., long range uniformity (LRU) becomes low.